PP Premier struggles to power valve amplifier

Hi Folks,

my first post, so please forgive any mistakes or incorrect assumptions.

I have a Power Plant Premier AC Regenerator, 240V (UK) version. It has run quietly and happily for years, supporting a record deck, tuner, CD player and a Roksan 85W per channel Caspian M2 integrated amplifier from the isozone 5 power amplifier socket. It’s a powerful amp. and I’ve been known to turn it up pretty loud.

A few months back, I replaced the amplifier with an all-valve Primaluna Evo 400 integrated unit, rated at about 35W per channel. It sounds amazing, and I much prefer it to the slightly harder sound of the Roksan (which of course is a transistor based amp.).

But. After plugging the valve amp into the PP (isozone 5 socket) and running it for maybe 10 minutes, the amplifier protection fuse blew. It’s a special slow-blow 1.6A fuse, and is intended to cope with the ‘normal’ power spike contingent (I guess) on the initial switch-on surge and/or the volume being turned up. If anyone’s immediate reaction is to blame the amplifier, you might want to consider that it runs like a dream straight off the standard UK 13A mains socket.

I don’t believe there is necessarily a fault with either unit, but there may be something about valve amplifiers that makes them harder to run from a regenerator power supply.

I’d welcome your thoughts on the subject. There is one other point: when I power up the PP (without switching anything else on), the transformers make an audible hum. Should they?

Hope I haven’t bored you.


John M.

1 Like

Welcome @John_Moulding !

Hi John,

Welcome to the forums.

I reviewed the Manual for that power plant, as I assume you did, and couldn’t find anything in it, especially the troubleshooting section) about this problem. Hopefully, @jamesh or someone who owns one of these power plants can provide more details.

That said, I have read that some power amplifiers sound better when connected to the mains power instead of a power plant. Before you drive yourself nuts trying to fix this “problem,” I recommend trying an experiment.

Connect the power amplifier to your mains and run it for a few hours taking note of the sound quality. Then, as fast as possible, power off the power amp, connect it to the power plant, then power it back on. Listen to the last music track again and ask yourself which way sounds better. If it sounds better when connected to the mains, don’t worry that you cannot get it to work correctly on the powerplant, as your best sound quality comes from the mains anyway.

Best of luck to you on this.

Welcome John! It sounds to me like the new amp might not like being plugged into the PPP. An incompatibility potentially.

It doesn’t really sound like it to me but you could test if you’re driving the PPP a little too hard with the new amp now. To test this, unplug everything from the PPP but the amp and see if the fuse still pops.

The PPP and other PowerPlants don’t have an inherent issue driving tube/valve amps but as mycrowave points out, there is potential that the new amp would rather be plugged straight into the wall.

Hi and welcome you seem to have the spec’s wrong on you Primaluna 400 . If you are running EL34 tube’s it is 70 watts per channel and power consumption of 470 watts continuously. This may be the problem. Great integrated amp. Enjoy


Absolutely correct, my bad. I described it poorly.

However, I would have thought that the power amp output on the PP should be able to provide a lot more than 470W continuous. The manual quotes up to 1500W, although I note the “up to”… presumably for brief bursts.

Thanks for the correction.

No problem, if you have anything else running on your PP You have to factor in the power consumption of those components. I have a P20 and with just running my primaluna Dialogue pre amp and mono amps I am running the p20 at 50 percent. 1170 watts.
Also just make sure you have your amp plugged into the high current outlet on your PP .